Asthma in children is often under-diagnosed which can be a serious problem since delays in the initiation of therapy is deleterious. Despite recent increases in asthma prevalence and morbidity in children, especially African American children, valid and reliable asthma screening measures have not been developed. Most asthma screening programs rely solely on responses to symptoms questionnaires. These programs identify large numbers of children as "possible asthma" who do not truly have the disease. The University of Alabama at Birmingham (UAB) School Based Asthma Screening Program overcomes this disadvantage by using a multi-stage screening procedure composed of a questionnaire, baseline spirometry, and an exercise challenge test. Previous research in our UAB School Based Asthma Intervention Study (funded by NHLBI) has shown that screening for asthma in a predominantly African American elementary school population can identify previously undiagnosed cases of asthma. These data show that 20 percent of asthmatics in this population were undiagnosed prior to the screening procedure, indicating a substantial burden of undiagnosed asthma in children. The primary aim of this project is to calculate the sensitivity and specificity of the UAB multi-stage asthma screening procedure. Several secondary aims will also be accomplished. These aims are: to refine the asthma symptoms questionnaire by identifying questions most predictive of an asthma diagnosis; and to determine the effect of respondent (parent or child) on reports of asthma symptoms. The validation of a simple, field-based asthma screening program will be a valuable tool in the identification of children with asthma. Such screening procedures can lead to decreases in asthma morbidity and mortality by identifying children with undiagnosed asthma.